New Kid in the Family
by shinee2007
Summary: As Tsuna and Lambo walked down the alley, they found a boy. Covered in blood. 4-shot. Warning: OC included.
1. Prologue

**Hi again!**

**So, I'm starting another multichapter story! **

**Enjoy~**

* * *

Tsuna-nii and I were walking along the neighborhood when we saw a little boy covered in blood. He wasn't just an ordinary little boy. Even I could tell that he wasn't. His eyes were emotionless; absolutely emotionless. It was the eyes of a skilled hitman. It wasn't quite level of Reborn's but it was very close.

The little boy stared at the ground and then as if he wasn't the same person from seconds before, he cried. The emotionless little boy was no longer in front of us but a crying little boy replaced him.

Tsuna-nii blinked then quickly ran to the boy's side. I followed him curiously and took a look at him from behind Tsuna-nii.

He was completely covered in blood. Most of the blood was dry but there were some parts where it was wet. Some looked days old and others looked fresh. As far as I could see, the little boy was not injured at all. The only part of his body I could clearly see was the tear streaks on his face.

"Hey… Hey, it's okay. Stop crying… There, there…" Tsuna-nii patted the dirty brown hair that was also dripping with wet blood.

The little boy flinched visibly. He lifted his head and stared at Tsuna-nii and me very carefully. After observing us for few minutes, he relaxed. His tense shoulders relaxed but his guards were not down. Why, I could not understand at all.

"Hey, little boy… Can you tell this onii-chan what your name is?" Tsuna-nii asked very gently while putting his hands on the little boy's shoulders.

"Ka…oru…" I could barely hear him whisper but heard him nevertheless.

Tsuna-nii, however, looked very confused and asked, "Can you please say that again?"

"His name is Kaoru, Tsuna-nii." I sighed as I ruffled my own hair.

Tsuna-nii made a small 'o' with his mouth and smiled apologetically at Kaoru. "Well, we have to get you cleaned up first… Can you come over to my house for a bit? Is that okay with you?"

Kaoru nodded and gave a small smile.

* * *

**This is just a prologue! Just like my other story, the chapters will be way longer! :D**

**Thank you for reading! **

**Please review! Your reviews... keep me writing! **

**Disclaimer: I do NOT own KHR. Thank you. **


	2. Chapter 1

**Thank you for your reviews! I really appreciate it! *bows* **

**Well, here is the next chapter! Enjoy~**

* * *

'Typical Tsuna-nii. He can't leave a child alone when they need something.' I thought with a small smile on my face. Then, I remembered the apathetic emotionless face the little boy had earlier but I brushed it off. 'It's probably nothing.'

Tsuna-nii and I walked Kaoru to our house silently. He and I had a tacit agreement never to question Kaoru too much.

* * *

When we arrived to our house, Kaoru froze at the entrance and stared at us questioningly as if he didn't know what to do.

I just opened the door and walked in. "Tadaima." I called out lazily. Then I turned around and motioned Kaoru to come in too. Tsuna-nii guided him from the back and Kaoru stepped in the room carefully, fully alarmed.

"Let's get you washed up, Kaoru!" Tsuna-nii said cheerfully and he disappeared up the stairs towards the bathroom.

I quickly followed also with curiosity.

Tsuna-nii ushered Kaoru into the bathroom and said, "Ne, Kaoru, why don't I help you get the blood off your body?"

Kaoru blushed and nodded quickly and they both disappeared behind the door of the bathroom. The shower was running and soft giggles came from the closed door. I leaned the wall behind me and waited for them to finish.

When the door opened, I could finally see what Kaoru really looked like. His hair was blonde with ruby red eyes.

Wait…

Weren't his eyes blue before? How did it change in those few minutes?

I crouched to Kaoru's eye level and asked, "Hey, how old are you?"

"T-Ten…" Kaoru stammered out as he continued to stare down at his feet. He fidgeted under my gaze and I stood up.

"…Tsuna-ni…" I called out

"Yes?"

"Isn't he too skinny and small to be a ten year old? Was he underfed or something?" I whispered to Tsuna-nii so Kaoru couldn't hear me.

"I don't know… but I don't think he should go back to his… home…" He whispered back.

"Do you think…"

"No. He can't be." Tsuna-nii cut me off.

"But you saw him in blood, Tsuna-nii. Blood. Why else would he have blood on himself?" I demanded.

"Eto…" We both looked at the little boy and saw him tilt his head. "What are you talking about?"

Tsuna-nii crouched down and smiled. "Nothing, Kaoru. I have a question. Do you think you can answer it for oniichan?"

Kaoru nodded his head and asked, "What is it, oniichan?"

"What's your last name?"

"I don't have a last name…" Kaoru answered as his head drooped. "I'm sorry, oniichan…"

Tsuna-nii shook his head and said, "That's fine! I was just curious, that's all." He smiled warmly at the young boy.

Kaoru's eyes were now blue again. I didn't understand. First it was blue, then red, and now blue again? How is this possible?

"Kaoru, do you want to live here from now on? I mean, I don't think you have a place to go to so…" Tsuna-nii trailed off.

"Can I?" Kaoru asked excitedly. "Can I really, oniichan?"

"I don't think kaa-san will mind feeding one extra mouth and I have other children in this house, including Lambo, so I don't see why not." Tsuna-nii smiled as he pointed at me.

I shrugged and said, "Yare yare. One more person in this house won't hurt anyone."

* * *

That night, Tsuna-nii gathered all his guardians including me into his room. Everyone looked either confused or pissed off at the late hour and Tsuna-nii's serious expression made me even more curious.

"Does this meeting concern Kaoru, Tsuna-nii?" I asked with my arms crossed as I leaned on the wall.

"Yes, Lambo, it is about that." Tsuna-nii answered.

Everyone looked confused now.

"Kaoru. Don't know his last name but Tsuna-nii and I found him on the street crying so we brought him home. Tsuna-nii asked him if he wanted to stay at our house and he agreed." I answered for all their silent questions.

"So… what's the problem?" Takeshi-nii asked.

Hayato-nii smacked Takeshi-nii on the head and shouted, "The problem is, baseball idiot, that that Kaoru kid might be an assassin hired by some mafia!"

"No, he's not a hired assassin." Tsuna-nii spoke up with firm voice and a boss aura that I rarely feel around him.

I protested, "There is a high possibility that he is, Tsuna-nii!"

"Just because he was covered with blood when we found him does not mean he is a mafia." Tsuna-nii said firmly. I knew just then that he wouldn't give in. I just knew, but I had to try. He looks innocent but… I have this feeling that Kaoru is not a normal boy.

I tried to protest again. "I know that you have soft spots for little children, Tsuna-nii, but he's not an ordinary child. He's not clueless or innocent! That boy is too suspicious! Yes, he is a little child. He is ten years old, but I was five when I came to this house as an assassin. Age does not matter in the world of mafia." I looked down and continued with a bitter tone. "Age… never matters to the adults of mafia."

"Kufufufufu… I agree with the cow child right there. Age doesn't matter in our world. Age 10? My first kill was when I was only six years old. That boy sounds very much like an assassin." Mukuro-nii leaned on a wall while smirking.

"Sawada! That boy sounds extremely innocent!" Ryohei-nii shouted with fists in the air. "I say you extremely keep him!"

"Shut up, turf-top!" Hayato-nii stated as he glared at Ryohei-nii. Then, he turned to Tsuna-nii and pleaded, "Jyudaime, that Kaoru kid sounds like an assassin. Please let me get rid of him."

"Ahahahaha! I want to meet Kaoru and teach him baseball!" Takeshi-nii laughed with carefree tone.

It was split into three groups. Mukuro-nii and Kyoya-nii did not care if Kaoru stayed or not, Chrome-nee, Takeshi-nii, and Ryohei-nii wanted Kaoru to stay, and Hayato-nii and I did not want Kaoru to stay. We, minus Mukuro-nii and Kyoya-nii, kept on shouting our opinions to Tsuna-nii.

Tsuna-nii slammed his fist on the wall next to him and yelled, "Be quiet!"

We all fell silent and looked at Tsuna-nii. "Since majority of us don't care or want Kaoru to stay, Kaoru will stay in this house and it is final. Is that understood?"

Kyoya-nii walked away after saying, "hn.", while Mukuro-nii just laughed creepily and disappeared using his illusions. Takeshi-nii and Ryohei-nii laughed and put fist in the air, and lastly, Hayato-nii and I just muttered, "Hai…"

It was official. Kaoru was going to stay .

* * *

I did not like this. Kaoru was getting all the attention because he's the youngest and needs more care from others! I was supposed to eat the candy and ice cream he was eating now. I was supposed to get the hug mama was giving now. I was supposed to have that blanket that he was using to take a nap with!

He's taking everything from me. Attention, care, and most of all, love was getting taken away from me. Nobody cares about me now that I'm not the youngest. I hate this.

Everyone was watching Kaoru closely, except for Tsuna-nii, Ryohei-nii, and Takeshi-nii. I could tell Chrome-nee was wary of Kaoru at first, but after few days, she gradually warmed up. Even Hayato-nii was being nice to him! Why? Am I the only one that thinks he's dangerous now?

I pulled Hayato-nii aside and whispered, "Hayato-nii. Kaoru might be an assassin! Why are you being so nice to him? He might hurt Tsuna-nii!"

He looked at me weirdly. "He's not that bad, Ahoushi. At first, I did think that he might be an assassin, but the way he acts and speaks does not sound fake. The feeling he is expressing, happiness, sadness, afraid, all do not look fake. Even a top class assassin can't give off that vibe. He's okay."

I growled in frustration.

"I know what it is." He said with a smug expression.

I glared at him. "What."

"You're jealous." Hayato-nii smirked.

I looked at him with exasperated expression. "I am **not**!"

"Yeah, yeah." He said and walked away.

"I am NOT jealous, Bakadera!" I shouted.

"Whatever you say, Ahoushi."

'Great. No one's in my side now. Everyone likes Kaoru and is not one bit suspicious of him. Just great.' I thought as I trudged into the house while ruffling my hair.

* * *

A small ruffling sound woke me up. I opened my right eye and saw a glimpse of Kaoru stepping out of his bed and walking out the door.

'Bathroom, I guess…' I thought and closed my eyes again but then a flash of Kaoru's eye color ran across my mind. Jet black. His eyes were black like Reborn's. His atmosphere was like Reborn's.

Chills ran down my back and I got out of bed, following Kaoru. He went in Tsuna-nii's room.

I peeked in the room. My eyes widened. A knife was glinting in the moonlight. Knife held by Kaoru, aiming at Tsuna-nii.

* * *

**Thank you for reading! I hope you enjoyed reading this!**

**Leave a review for me, ne? I would love to hear your opinion about this! :D**

**Disclaimer: I do NOT own KHR or any of its characters. **


	3. Chapter 2

**I'm so sorry guys for the long wait! I had no clue what to put on this chapter! DX**

**I hope you enjoy reading!**

**Disclaimer: I do NOT own KHR or any of its characters**

* * *

I didn't think at all and acted fast. Before Kaoru could really stab Tsuna-nii, I ran into the room and tackled him to the ground. The knife skidded across the room after slitting my left arm. I bit my bottom lip so I could refrain from yelping. With my body on top of Kaoru's belly, I grabbed his shirt and my other hand, ready to strike his face.

Kaoru struggled and kicked my back with his legs. It caught me off guard and I was the one on the bottom now.

"Tch. I didn't get any orders to kill you and **he **likes you so I can't kill you now." Kaoru clicked his tongue and got off of me.

My eyes became slit. "Mission? What do you mean?"

He grinned manically. He put his hand on his hip and wiggled his finger in front of me. "That is for you," He poked my chest, "to find out."

I growled and said through my teeth, "Tell me."

"Nu uh. I can't tell you. Sorry." He coldly smiled and saluted me. "Bye, **Lambo-niichan**"

I once again tackled him to the ground but just as I did that, Kaoru's jet black eyes faded into a sky blue color. With a daze look, he called out, "Lambo-niisan? What's wrong? Are you hurt?" He looked at my arm and gasped. "Is that blood?"

I stood up from his body and walked up to the knife that was few feet away from us. I picked it up and stomped out of the room. "Go back to our room and sleep." I ordered him.

"Okay…"

* * *

I threw the bloody kitchen knife into the kitchen sink and rinsed it off so nobody would suspect a thing. Then, I put the knife back in where it was supposed to be.

While holding my left arm from dripping blood, I slowly walked towards Ryohei-nii's room to get my arms treated. Sharp pain in my right shoulder made me wince a little. I guess it got dislocated during the struggle. I held my wound from the knife with my right hand.

* * *

In front of my destination, I called out for Ryohei-nii gently. "Ryohei-nii… Can you come out for a second?" Then, I knocked on the door three times.

Inside, I heard a ruffling noise inside. A few seconds later, he came out of his room, ruffling his hair and only one eye barely open. "What's wrong, La-"

His eyes widened and gently reached out for my left arm. I slightly winced but did not pull away. I had a closer look to the wound and I was quite surprised how deep it was. The only reason blood didn't drip that much was because my pajamas absorbed the blood and I mainly covered the wound with my hand.

"How did this happen?" He quickly asked. "What happened? Are you-"

I inspected the halls nervously. "Do you mind if I go in your room?"

Ryohei-nii quickly welcomed me into his room. "Of course, Lambo! Come in."

I went in his room and sat down on his sofa but winced at the touch of it. My arm trembled and I tried to stop it with my other hand. "Ryohei-nii… Please heal my arms…"

He came to me and started using his sun flames on my open wound. I watched the wound close slowly. Then, it became a scar and the scar disappeared within time. I breathed out the air that I didn't notice I was holding.

As for my other arm, Ryohei-nii observed what the problem was. "It's… dislocated… I have to pop this shoulder back in, okay?"

I nodded slowly.

"It's going to hurt a little, Lambo. Brace yourself." He warned me. He grabbed my shoulder then counted off from one. I bit my lips, trying not to cry out from the pain. With a small 'pop', my shoulder was now free from internal pain.

"Thank you, niichan. I will be going now." I bowed and reached out for the exit.

Ryohei-nii's worried tone stopped me. "Can you tell me where you got those wounds? In the middle of the night, no less."

"No. I can't tell you. You won't believe me anyways." Just as I walked out of the room, I halted and looked back. "Don't you dare tell Tsuna-nii about my wounds, Ryohei-nii. I don't want to worry him with something as trivial as this."

"You know that I will have to tell him some time in the future." He sighed as he ruffled his own hair. "Or when he finds out, he will kill me."

"He won't find out if you don't tell him." I glared. "So don't tell him. This needs to be a secret from everyone."

After a short silence, he finally gave up. "Fine. I will not speak of this to Tsuna."

"Swear that you won't tell anyone about this." My glare became pleading eyes. "No one is to know about this, Ryohei-nii. The only reason I came here is because I couldn't have gotten a wound this serious overnight and they would ask me too many questions!"

"But Lambo! Someone needs to know!" He protested. "At least tell me… Please?"

I stomped my foot in a frustrated way. "I told you; you will never believe me! You'll think I lied to you!" I stomped out of the room.

"Don't tell others or I won't ever talk to you ever again!" I shouted as I slammed the door close behind me.

* * *

Ever since that night, I have been observing Kaoru nonstop. The sleep I have been getting became less and less. Once in a while, color of Kaoru's eyes would change. Whenever he thinks nobody is looking, he stares at Tsuna-nii with his cold jet black eyes.

One day, Tsuna-nii came up to me and asked, "Lambo, are you okay? You seem… different."

I yawned softly and said, "It's nothing. I'm just tired."

"Are you sure?"

I nodded. 'I will let nothing hurt Tsuna-nii. Nothing. He saved me from darkness of the world. He protected me throughout my life. It's my turn to protect him, as his lightning guardian. I will be his lightning rod. I will.'

"I'm okay, Tsuna-nii. Thank you for worrying." I smiled and walked away. 'I won't let him get hurt no matter what.'

* * *

**Thank you for reading this chapter! I really appreciate it! **

**Please review! I would LOVE to hear what you think about this story!**


	4. Chapter 3

**I'm so sorry for being so late! **

**Thank you for all of your reviews. I really really really really really appreciate them! **

**Please enjoy!**

* * *

I decided. I'll tell I-Pin about Kaoru and what I saw that night. She'll believe me. After all, we were best friends for ages. She'll believe me more than Kaoru.

"I-Pin, can I talk to you?" I walked up to her.

She looked startled that I didn't call her by her nickname as I always did. "Sure, Lambo. What is it?"

I looked down at my feet and whispered, "It's about… Kaoru." I looked at her nervously.

My eyes darted to the said boy for a second, who met my eyes and smiled at me.

"What about him?" she asked. She tilted her head.

"Kaoru… He's an assassin that is trying to kill Tsuna-nii. I saw him trying to stab him few weeks ago and that's why I am observing him right now." I said very quickly.

I-Pin's expression was unreadable. She looked at the ground and her shoulders shook. Was she mad at Kaoru now? Will she believe me?

"I-Pin…" I held onto her shoulder. "Liste-"

"Pfft…"

"Huh?"

"Lambo… That is the most hilarious thing I have ever heard in my life!" She laughed, clutching her stomach. "You could become a comedian with this kind of joke! I mean, Kaoru, an assassin? He's innocent as a sheep! He's more naïve than Takeshi-nii was back when he was in middle school!"

The sense of betrayal washed all over me. I had hoped at least I-Pin believed me, but no. She didn't. I forced a grin. "Yeah, I know right? Dang, you figured it out!"

"Was today April Fool's Day?" She asked me. "Oh wait… Today isn't April 1st! Today is September 11th! It's another seven months away!"

"Hahaha! No, today is 'Try to Trick Opposite Gender Day', or 'TTOG' for short! I made it up weeks ago and tried really hard to trick you girls." I laughed along with her.

"Aha. That was a good one." She smiled at me wiping her tear that welled up in her eye.

I forced a grin again. "I can't believe you didn't fall for that one though! After all, I practiced this line so many times in front of a mirror, trying to look really serious and all!"

"I almost fell for it and it was really good, Lambo!" I-Pin giggled. "I really almost fell for it. If I didn't know Kaoru or you any better, I totally would have fallen for that one."

"Well then, bye. I have to go find Chrome-nee to trick her this time." I waved a goodbye. "Don't tell anyone about this holiday though! And do it for yourself too! Go and trick a boy out there." I walked out of the room with carefreeness. When I closed the door to my room, I leaned on it and grimaced.

'She didn't believe me after all…' I thought. 'If she didn't believe me, nobody will believe me now… Nobody…'

I looked up determinably. 'I will protect Tsuna-nii by myself if I have to. I won't let him get hurt. And… this isn't just about Tsuna-nii now. Everyone is in danger because they won't suspect a thing that Kaoru is actually an assassin and when he does decide to attack… I will be the only one who will be ready for it.'

* * *

The next few days, I noticed that Kaoru's black eyes appeared more and more frequently and each time it did, he looked at Tsuna-nii maliciously. Then, he met my eyes that had a glare. He smirked and waved before the eyes turned blue again.

'He has two different personalities.' I realized. 'The blue eyed one is the innocent one where black eyed one is the one that is trying to harm Tsuna-nii. And the black eyes are appearing frequently nowadays. It seems like I don't have much time.'

"Lambo." A voice behind me startled me. I flinched and turned around to see Tsuna-nii. "Lambo… You're being restless these days. What's wrong?"

"It's really nothing."

Ryohei-nii walked up to me behind Tsuna-nii. "It began after **that **night, didn't it, Lambo? Tell me what happened."

I glared at Ryohei-nii. "I told you that it was nothing. Now, if you'll excuse me, I have some homework to do."

As I turned around, a hand on my shoulder stopped me. "Don't dismiss us like that, Lambo. As your boss, I have the right to know about this."

"I really am sorry, **boss**, but I have nothing to say." I spat back. 'You won't believe me anyway. You didn't listen to me back then. I know you won't listen to me now.'

"Lambo!" He stared at me like I said something he didn't expect. I guess I did, since I always apologized after hearing his boss tone. "I order you to tell me what you're keeping from me."

I stared at him with wide eyes. He never ordered me before; never. I turned stoic and expressionless. "Yes, boss." I answered with a monotone. "Kaoru tried to attack you few weeks ago, the day he came to our house. I stopped him and got injured. Then, I went to Ryohei-nii's room to get my injuries taken care of."

Tsuna-nii's eyes widened. "That's impossible! He's so small and innocent! Maybe you saw him incorrectly, or maybe you were just a little tired and saw someone else?"

"Or maybe, Kaoru really is a child assassin that is trying to end your life, Tsuna-nii!" I retorted in outrage. After a while of thinking, I whispered, "You know what? Forget it, Tsuna-nii. Forget what I said."

"Lambo…" Tsuna-nii started to reach out for my shoulders. I flinched and backed away. When he saw that, he stopped himself and finished, "It's just so hard to believe that, Lambo."

"Then don't believe me!" I stomped out of the room and shut the door behind me loudly. 'Just don't believe me, Tsuna-nii. Even if something happens to me, I will protect you because that is my job as a guardian. This will be my unofficial first mission: protect Tsuna-nii from Kaoru.'

* * *

Then a few more days later, everyone, including I-Pin, Bianchi, Fuuta, and Kaoru were in the living room together. We were having one of our family meetings to hang out. There still was some tension between me and the other guardians but I didn't care. I was just watching Kaoru; especially his eyes.

Then, the innocent blue eyes turned jet black and a maniacal cackle came out of Kaoru's mouth.

Tsuna-nii looked at him with a confused look. "Kaoru? What's wrong?"

"I can't believe…" Kaoru laughed so hard it seemed like he couldn't continue. "I can't believe… you guys didn't believe him."

Ryohei-nii widened his eyes. "No…"

"Yes." Kaoru smirked.

Out of the corner of my eye, I saw a glint of a metal object and automatically moved in front of Tsuna-nii. There was a loud 'bang' and next thing I knew, my stomach was pierced by a bullet. Pain erupted and I had to bite my bottom lip not to cry out.

No one moved. My breathing ragged and I clutched for my stomach where the sticky blood seeped through my fingers. Kaoru's eyes turned blue once again. He looked at me in shock and tears welled up again.

"Lambo-niichan!" he wailed, "Don't die… please! Lambo-niichan!" Kaoru dropped to his knees and with shaking hands, he shook me lightly, but even that light touch made me cough up blood.

Ryohei-nii ran to my side and laid me down properly. Then everyone else came and surrounded me. Kyoya-nii wasn't part of the circle, but he still was near; I could feel it. Ryohei-nii started to work on my wound. After he gingerly took the bullet out of my body, he poured his sun flame on the wound.

My eyesight became very hazy and could barely see anything anymore. Only thing that I could see was a ball of brown hair… Tsuna-nii.

"Tsuna…nii…" was the last thing I said until the darkness took over.

* * *

**Thank you very much for reading this!**

**Okay, this will sound like a pathetic excuse, but I really have a lot of things to do. Last 3 months, I was involved in Marching Band that took up most of my time and school just started a week ago. I found the time to write this because my teachers were generous and didn't give me many homework, but my updates will be EXTREMELY slow! I'm really sorry!**

**Disclaimer: I do NOT own KHR or any of its characters. **

**Please leave a review! I would love to know what you think about this!**


End file.
